Egg protein is often considered beneficial for supporting nail health, and there is a reasonable scientific basis for this claim. Human nails are primarily composed of keratin, a tough structural protein. Protein deficiency can lead to brittle or weak nails, and consuming high-quality dietary proteins provides the essential amino acids necessary for keratin synthesis. Egg protein, specifically, is regarded as a "complete" protein, meaning it contains all nine essential amino acids in proportions well-suited to human needs.

Several studies have linked adequate protein intake to healthy nail growth and strength, although there is limited direct clinical research focusing solely on egg protein and nail health. Nutritional analysis supports that individuals with protein malnutrition often exhibit nail abnormalities, such as spoon-shaped nails (koilonychia) or soft, thin nails. In addition, eggs are a source of other nutrients important for nails, such as biotin, though the evidence for biotin's effects is mixed and more relevant to supplementation in cases of deficiency.

While no studies have tested egg protein as a targeted intervention for nail health, the general scientific consensus is that consuming sufficient dietary protein, including that from eggs, is important for maintaining strong, healthy nails. Thus, the use of egg protein for this body system is supported by nutritional science, though not by specific clinical trials.